Active-matrix light emitting displays include drive electronics associated with each light emitting pixel for controlling the light output of the pixels. Active-matrix emissive display devices suffer from a number of difficulties. For example, as the emissive materials in the light emitters age, the materials change so that the light output from the light emitters will also change. In addition, it is problematic to manufacture such display devices and maintain a consistent uniformity across the entire display due to process control difficulties. Moreover, the materials employed in active-matrix emissive display devices change from one generation to the next, and the cost of creating a custom controller for each generation of material add significantly to the cost of the display devices.
The use of smart controllers capable of controlling a variety of similar devices and incorporating programmable elements is known. For example, U.S. Pat. No. 6,100,879 issued Aug. 8, 2000 to DaCosta discloses a system for controlling an active-matrix display using a smart controller with a programmable register on board. The approach proposed by DaCosta does not compensate for changes in the light output of the display over time, thus the problems noted above still exist.
There is a need, therefore, for a controller that overcomes the problems noted above.